Mechanical golfer



March 19, 1968 w. H. THOMPSON ET AL 3,373,612

MECHANICAL GOLFER 7 Sheets-Sheet 1 Filed Dec. 27, 1965 March 19, 1968. w. H. l'H OMPSON ET AL MECHANICAL GOLFER '7 Sheets-Sheet Filed Dec. 27', 1965 INVENTORS'.

a WW MMWM W A TTOPA/[F March 19, 1968 w. H. THOMPSON ET AL 3,373,612

MECHANICAL GOLFER 7 Sheets-Sheet 5 Filed Dec. 27, 1965 =INVENTORS W/LA/A/W-H THOMP-SOA/ B 11/44/444 .1 4145mm il lllllj k March 19, 1968 Filed Dec. 27, 1965 W. H. THOMPSON ET MECHANICAL GOLFER 7 Sheets-Sheet 4 IN V EN TORS' WWQMWW March 19, 1968 w. H. THOMPSON ET AL 3,373,612

MECHANICAL GOLFER Filed Dec. 27, 1965 '7 Sheets-Sheet 5 March 19, 1968 w. H. THOMPSON ET 3,373,512

MECHANICAL GOLFER Filed Dec. 27, 1965 7 Sheets-Sheet 6 mfl ill ll fl ll ll lfll I "Ill INL/ENTORS w/z 1/4/14 mo/Wso/v WWZWW% ABSTRACT OF THE DISCLOSURE A mechanical golfer having a club arm rotatably mounted upon a frame, the club arm having wrist means hinged freely on the free end of the club arm for pivotal movement with respect thereto within the radial plane. Grip means are provided on the wrist means for rolling movement about the axis of the club handle. Motor means move the club arm and the club in correspondence to the golfers backswing and automatically release the arm at the end of such backswing. Potential energy storing means then drive the club arm and the club downwardly through the foreswing with the club arm being braked so as to decelerate same during the followthrough portion of the swing.

This invention relates to a machine for hitting a golf ball with a golf club and more particularly relates to a machine of the afore-mentioned type capable of closely simulating the club swing of a competent golfer.

The present invention was developed to fill a need for a golf club swinging machine capable of producing a club swing closely similar to that of a competent golfer for use in testing golf clubs and balls and for assisting in determining the particular clubs best suited to the individual golfer.

Although a variety of golf club swinging devices are known, none is believed completely satisfactory for the above-mentioned purpose. For example, one known type of device intended primarily as an aid in teaching golf through demonstrating the preferred positions of substantially all the major skeletal parts of the human body from head to foot during the full cycle of ball address, backswing and so forth. Such devices are, understandably, relatively complex and expensive since they closely simulate the human skeleton in structure and movement and provide a pseudo-muscle system for driving the parts of the skeleton. Further, such devices generally cannot generate club head velocities and ball impact forces at a level of magnitude comparable to the performance of an average golfer and thus are generally not suitable for club and ball testing. Moreover, such devices cannot normally withstand, without undue wear and tear, the shocks and stresses imposed thereon by normal club acceleration and ball impact forces.

Other known devices provide only a substantially simplified club swing corresponding to only the relatively gross movements of a few major body parts or joints. More particularly, such prior devices have generally omitted some of the more subtle and yet important movements applied by the human golfer to the golf club, particularly movements of the wrist area, which contribute in large measure to the dynamics of a competently swung golf club. It would be expected, therefore, that such prior devices might give a distorted picture of the performance of a particular club or ball or club and 'ball combination used therewith and lead to error in prediction of the suitability of such equipment for the average golfer and and beyond that for a particular individual.

Accordingly, an object of this invention is to provide a mechanical golfing machine arranged for swinging a golf club and hitting a golf ball therewith in which the ited States Patent swing of the golf club closely simulates the club swing of a competent golfer.

A further object is to provide an apparatus, as aforesaid, capable of hitting a golf ball in a repeatable manner to any desired distance substantially up to the capability of the longest hitter in golf and capable of relatively highly precise targeting of the ball.

A further object is to provide an apparatus, as aforesaid, capable of duplicating the major golf club dynamics imposed by a competent golfer on a golf club during backswing, foreswing and followt-hrough.

A further object is to provide an apparatus, as aforesaid, capable of adjustment to simulate common faults in swing and to predictably demonstate the effects thereof upon ball path and which in this manner may be used in golf instruction or to assist in correcting the faults of individual golfers.

A further object is to provide an apparatus, as aforesaid, capable of use in testing and comparing existing and experimental clubs, e.g., for shaft and head quality, which is arranged for providing a variety of data including data comparing club head speed, ball impact point, club loft angle and ball path, which may be used as an aid in custom golf club building and in the improvement of commercial lines of golf clubs and which may be used in testing golf balls and particular combinations of ball and club.

A further object is to provide an apparatus, as aforesaid, which is adjustable for correctly positioning and swinging a wide variety of different types of clubs with respect to both form and speed and which is adaptable to all common types of woods and irons.

A further object is to provide an apparatus, as aforesaid, which can be used to determine the proper clubs for an individual based on analysis of his swing and on performance results of a variety of club swings by the mechanical golfing device when set for a swing similar to that of the golfer.

A further object is to provide an apparatus, as aforesaid, which is capable of being readily and relatively inexpensively manufactured, which requires only readily available materials or parts and which is well adapted either to large or small scale production.

A further object is to provide an apparatus, as aforesaid, which is capable of hitting a series of golf balls in rapid succession, which is simple to use and to adjust and which is relatively compact and easy to transport.

A further object is to provide an apparatus, as aforesaid, which is sturdy enough to withstand the shock and strain of repeated high speed club-ball impacts, which is capable of a long operating life under disadvantageous conditions with a minimum of maintenance and which is readily m'aintainable with only common tools and little or no instruction.

Other objects and purposes of this invention will be apparent to persons acquainted with apparatus of this general type upon reading the following specification and inspecting the accompanying drawings.

In the drawings:

FIGURE 1 is 'a side elevational view of a machine embodying the invention.

FIGURE 1A is an enlarged fragment of FIGURE 1.

FIGURE 2 is a view showing the front of the machine as taken along the line 11-11 of FIGURE 1.

FIGURE 3 is an enlarged, partially broken fragment of the machine embodying the invention taken from the opposite side thereof as FIGURE 1.

FIGURE 4 is a sectional view substantially as taken along the line IVlV of FIGURE 3.

FIGURE 5 is a sectional view generally taken on the line V-V of FIGURE 1A.

FIGURE 6 is an enlarged sectional view generally taken on the line VIVI of FIGURE 3.

FIGURE 7 is an enlarged, partially broken fragment of FIGURE 1A.

FIGURE 8 is a fragmentary view taken from the right side of FIGURE '7.

FIGURE 9 is a sectional view substantially taken on the line IXIX of FIGURE 7 and rotated in a clockwise direction through 90.

FIGURE 10 is a sectional view substantially as taken on the line XX of FIGURE 8 and rotated in a clockwise direction through 90.

FIGURE 11 is 'an enlarged fragment of FIGURE 3.

FIGURE 12 is an enlarged partially broken fragment of FIGURE 2 and discloses a modification thereof.

FIGURE 13 is a partially broken fragmentary sectional view substantially taken on the line XIII-XIII of FIGURE 12.

FIGURE 14 is 'a fragmentary sectional view substantially as taken on the line XIVXIV of FIGURE 13.

FIGURE 15 is a fragmentary side elevational view corresponding to FIGURE 1A and disclosing a further modification.

FIGURE 16 is a fragmentary oblique view of the modified apparatus of FIGURE 15.

FIGURE 17 is 'an enlarged fragment of FIGURE 6 showing a further modification.

FIGURE 18 is a partially broken sectional view taken substantailly on the line XVIII-XVIII of FIGURE 17.

FIGURE 19 is a side elevational view partially in central section of a modified club handle gripping device.

FIGURE 20 is a sectional view substantially as taken on the line XXXX of FIGURE 19.

FIGURE 21 is a diagrammatic view of a club head speed indicating device disclosed broadly in FIGURES 1 and 2 above.

FIGURE 22 discloses a modification of the apparatus of FIGURE 21.

Certain terminology will be used in the following description for convenience in reference only and will not be limiting. The words upwardly, downwardly, rightwardly and leftwardly will designate directions in the drawings to which reference is made. The word front will refer to the rightward end of the apparatus seen in FIGURE 1. The words inwardly and outwardly will refer to directions toward and away from, respectively, the geometric center of the device and designated parts thereof. Said terminology will include the words above specifically mentioned, derivatives thereof and words of similar import.

General description In general, the objects and purposes of the invention are met by providing an apparatus for swinging a golf club through a sequence of backswing, foreswing and followthrough in a manner of simulating the swing of a competent golfer which includes a frame and a main shaft rotatably mounted on the frame. A club arm is fixed to and extends radially from the end of the mainshaft for rotation therewith within a radial plane. Wrist means are hinged freely on the free end of the arm for pivotal movement with respect thereto within the radial plane. Means for releasably gripping the handle of a golf club are rotatably fixed to the wrist means for rolling movement with respect thereto generally about the axis of the club handle. Interacting means on the free arm end and gripping means control the roll position of the gripping means on the wrist means as a function of the hinged position of the wrist means on the end of the arm. Thus as the club pivots within the radial plane upon the hinge connection of the wrist means to the free end of the arm, it is rotated about the axis of its handle to stimulate the wrist hinging and rolling action imposed on a golf club by a competent golfer during the swing.

Motor means are provided to move the club arm and club in correspondence to a golfers backswing and automatically release the arm at the end of such backswing. Potential energy storing means, energized during the backswing, drive the arm and hence the club downwardly through the foreswing after release thereof by said motor means. The club, which preferably has been manually cocked to an angled position with respect to the arm corresponding to the normal cocked position of the club at the top of the swing of a competent golfer, freely responds to centrifugal force and thereby is swung to and through a position in alignment with the club arm in the area of the ball to stimulate the wrist snap of a competent golfer. Suitable brake means are preferably included to gradually decelerate the club head during the followthrou-gh portion of the swing.

Detailed description Apparatus 10 comprising a preferred embodiment of the invention is disclosed in FIGURES 1-11. The apparatus 10 includes a generally horizontal base 11 (FIGURES 13) upon which is mounted a frame 12. Frame 12 comprises a sloped central beam 13. The forward end of the beam 13 is elevated and carried by a downwardly diverging pair of legs 16 and 17 preferably defining a plane at right angles to the beam 12 and, hence, sloped at an angle A with respect to the base 11. The lower ends of the legs 16 and 17 are supported just above the base 11 on brackets 18 and 19 for pivotal movement about a common axis in the plane thereof. An upstanding arcuate member 21 is supported on the base 11 adjacent the lower, rearward end of the beam 13. The rear end of the beam 13 is adjustably fixed to the arcuate member 21 so that raising or lowering the rearward end of the beam 13 along the arcuate member 21 alters the angle A above mentioned and the angle B which the central beam 13 makes with the base 11. In the particular embodiment shown, the arcuate member 21 is provided with a plurality of spaced holes 22 arranged along an are centered on the pivot axis of the legs 16 and 17, the beam 13 being secured to the arcuate member 21 at any desired location upon a suitable pin 23 extending through one of the holes 22.

A mounting block 26 (FIGURE 1A) is fixed to and extends generally downwardly from the forward end of the central beam 13 along the plane of the legs 16 and 17. Fixed to the block 26 is an inverted, U-shaped yoke 27 comprising a downwardly opening channel-shaped bight and a pair of legs which parallel the plane of the legs 16 and 17 and are spaced longitudinally of the central beam 13. A main shaft 28 parallels the central beam 13 and extends through and is rotatably supported by bearings 31 and 32 carried by the lower ends of respective legs of the yoke 28. In the particular embodiment shown, the main shaft 28 is mounted slightly to the left of the central plane of the frame 12 as seen in FIGURE 2.

The front end of the haft 28 extends beyond the bearing 31 and, hence, beyond the plane of the legs 16 and 17. A radially extending club arm 34 is fixed at its upper end, here by screws 36 (FIGURE 3), to the front end of the shaft 28 for rotation therewith and circumferential ad justment thereon. A wrist device 38, described hereinafter in detail, is secured to the lower end of the club arm 34 and releasably grips the hand grip G of a golf club C of any desired kind. The club arm 34 and the shaft S of the gold club C are arranged to move in a common plane perpendicular to the axis of the shaft 28. A platform 39 is supported on the base 11 in front of the legs 16 and 17 and just below the path of swing of the head H of the golf club C for supporting a ball B in such a position that it will be struck by the club head H as the club C is swung by the arm 34. The apparatus 10 is intended to swing the club arm 34 and therewith the club C in a clockwise direction as seen in FIGURE 2 to simulate the backswing of the normal golf stroke, then to urge the club arm and club downwardly in a counterclockwise direction toward.

the ball B to simulate the foreswing portion of a golf stroke and then, after the 'ball is struck by the head H of the club C, to allow the club arm 34 and club C to travel through the followthrough portion of a normal golf club swing.

The apparatus includes a drive system generally indicated at 41 (FIGURES 1-4). The drive system 41 comprises a motor 42 pendently supported beneath the central beam 13 on a mount 43 and having a shaft 44 which parallels and lies beneath the central beam 13. The motor 42 is preferably an electric motor supplied with electrical current through a normally open, manually actuable switch 46 from suitable current supply terminals 47 and 48 which preferably constitute a conventional 110 volt A.C. output. The shaft 43 of the motor 42 drives a speed reducing gear train generally indicated at 49. The gear train is mounted on a bracket 51 which parallels the plane of the legs 16 and 17 and is placed between the motor 42 and mounting block 26. The gear train 49 includes a drive pinion 52 fixed to the motor shaft 43 which drives an enlarged countershaft input gear 53. The countershaft input gear 53 and a countershaft output gear 54 of reduced diameter are disposed on opposite sides of the bracket 51 and are fixed for rotation on a countershaft 56 rotatably mounted with respect to the lower end of said bracket 51. An externally toothed drive disk 57 of relatively large diameter meshes with the countershaft output gear 54 and is rotatably supported in a plane parallel to that of the legs 16 and 17 on the bracket 51. The rotational axis of the disk 57 is spaced above and to the right (FIGURE 2) of the axis of the main shaft 28. The drive disk 57 is rotated by the motor 42 in a clockwise direction as seen in FIGURES 2 and 4. The drive disk 57 has a drive pin 58 fixed to and extending generally forwardly from the front face thereof near the periphery thereof. In the particular embodiment shown, the drive pin 58 is of generally circular cross section except for a fiat 59 which, as seen in FIGURE 4, faces somewhat to the right of the center of the disk 57.

A drive arm 61 is rigidly afiixed to the rearward end of the shaft 28 behind the bearing 32 and extends radially and generally downwardly therefrom preferably in substantial parallelism with the club arm 34. The drive arm 61 is located near the forward face of the drive disk 57 and in the path of the drive pin 58 during the lower, leftward (FIGURE 4) portion of its rotation. More particularly, the drive arm 61, when near its downwardly extending position indicated in the solid lines of FIGURE 4, will be engaged by the revolving drive pin 58 and will be pivoted thereby for rotating the shaft 28 in a clockwise direction. Due to the eccentric location of the axes of the drive disk 57 and main shaft 28, the revolving drive pin 58 gradually moves radially outwardly from the shaft 28 along the drive arm 61 until it reaches the end of such drive arm, such position being indicated at broken lines in FIGURE 4. Eventually, the end of the drive arm 61 slides off the edge of the rounded portion of the revolving drive pin and may then drop freely past the fiat 59. In the particular embodiment shown, the arm 61 is lifted to a position about above the horizontal by the pin 58 prior to its release. However, if contemplated that further openings, indicated in broken lines at 62, may be furnished in the disk 57 for releasably receiving the drive pin 58 in alternative fixed location therein to vary the angle of inclination of the drive arm 61 when released by the pin 58.

As shown in FIGURE 3, a spring arm 66 is supported on and for rotation with respect to the main shaft 28 intermediate the main shaft bearings 31 and 32 by suitable bearings 67 and 68. The spring arm 66 is in the particular embodiment shown substantially the same length as the drive arm 61 and is located closely adjacent the rearward bearings 32 and, hence, relatively close to the drive arm 61. A spring 71, here an elongated helical tension spring, is connected between anchor means 70 (FIGURE 6) on the spring arm 66 and the frame for urging the spring arm 66 downwardly into and, if desired, somewhat past its depending solid line position of FIGURE 5 from its elevated broken line position of FIGURE 5. In the particular embodiment shown, the lower end of the spring 71 preferablyadjustably connects to the rightward leg 17 as seen in FIGURE 2 at a point near to but spaced from the bracket 19. The lower end of the spring 71 is here secured to the leg 17 by a bolt 72 alternatively positionable in any one of several holes 73 extending through and spaced along the leg 17. The upper end of the spring 71 is coiled around a generally cylindrical core 74 of the anchor means 70 at the center thereof and is snugly disposed between an axially spaced pair of radial flanges 76. The core 74 is equipped with bushings 77 which mount the core 74 snugly but rotatably upon a bolt 78 which extends transversely through the spring arm 66. The bolt 78 is alternatively inserta ble through a plurality of holes 79 (FIGURE 5) spaced along the length of the spring arm 66 to allow varying of the length of the lever arm upon which such spring works. By varying the locations of the spring ends with respect to the holes 73 and 79, the force exerted on the arm 66 by the spring 71 can be varied for any desired position of the spring arm, any fatigue in the spring can be compensated for and the spring arm position versus spring tension characteristic can be altered.

Thus, the adjustment of the spring ends in the holes 73 and 79 together with the adjustment of the pin 59 and holes 62 and angular adjustment of the club arm 34 of the shaft 28 together with the possibility of readily replacing the spring 71 by a stronger or weaker one, allows considerable variation in the top point of the backswing, the instantaneous torque exerted on the club arm at any point in its swing by the spring and the point at which the spring ceases to exert further accelerating torque on the club arm.

An overrunning one-way latch 81 (FIGURES 1A, 3, 5 and 6) on the spring arm 66 allows the drive arm 61 to move the spring arm 66 therewith through the backswing substantially to their respective broken line positions of FIGURES 4 and 5 for tensioning the spring 71. The latch 81 further allows the spring arm 66, upon release of the drive arm 61 by the pin 59, to accelerate the drive arm 61 and club arm 34 through the foreswing, that is, from the broken line positions through the solid line positions of FIGURES 2, 4 and 5. Still further, the latch allows the drive arm 61 to move freely past the spring into the followthrough portion of the stroke as the spring arm swings past the spring 71 and is retarded thereby.

In the particular embodiment shown in FIGURE 6, the latch 81 comprises a bracket 82 on the side of the spring arm 66 away from the spring 71 near the lower end thereof, such bracket 82 generally being U-shaped and supporting a pin 83. A latch arm 84 is mounted intermediate its ends pivotally of the bracket 82 by the pin 83. The rearward end 85 of the latch arm 84 extends into the path of the drive arm 61. The forward end of the latch arm 84 is connected by a tension spring 86 to a boss 87 fixed to the face of the spring arm 66 forwardly of the bracket 82, such spring 86 extending at an angle forwardly and toward the spring 71 to urge the latch arm 84 in a counterclockwise (FIGURE 6) direction. An abutment 88 is disposed between the boss 87 and bracket 82 for limiting counterclockwise movement of the latch arm 84 to a position generally parallel to the adjacent face of the spring arm. As seen in FIGURE 6, the latch arm 84 positively prevents movement of the spring arm 66 past the drive arm 61 in one direction (downward in the drawing) so that the drive arm 61 carries the spring arm 66 through the backswing and the spring arm carries't'he drive arm 61 through the foreswing. Should the drive arm move away from the latch arm 84 through a full circle, the face 89 of the drive arm will eventually strike the rearwardly extending end 85 of the latch arm on the other side thereof and pivotally displace the latch arm against the tensioning spring 86 to move therepast.

A brake 91 (FIGURE 11) is preferably provided for decelerating the club arm 34 during followthrough. The brake 91 preferably does not act during the foreswing and backswing portions of the operation. In the particular embodiment shown in FIGURES 3 and 11, the brake 9 comprises a generally cylindrical shell 92 snugly surrounding the shaft 28 and secured thereto for rotation therewith by any convenient means, here comprising a pin 93. The shell 92 is bounded at its forward end by a shoulder 94 on the shaft 28 adjacent the forward leg of the yoke 27. An integral bracket 96 extends generally radially from the shell 92 intermediate the ends thereof. A generally T- shaped actuator 97 has a leg 98 extending substantially radially inwardly toward the shaft 28 and pivotally supported on the bracket 96. A tension spring 99 extends axially along the shaft between the inner end of the leg 98 and a boss 101 on the sleeve 92 adjacent the forward end thereof. Thus, the spring 99 urges the actuator 97 in a clockwise direction as seen in FIGURE 11. The T-shaped actuator 97 has a crosshead at the outer end of the leg 98 which extends generally parallel to the axis of the shaft 28, the forward end 102 of such crosshead being weighted, if desired, so that rotation of the shaft tends to pivot the actuator 97 more strongly in a clockwise direction as the speed of rotation increases due to centrifugal force. The rearward end 103 is relatively short and is rounded on its lower face for bearing against a brake disk 104 splined to the rearward end of the sleeve 92. An annular brake ring 106 is aflixed, here by welding, to the forward face of the spring arm 66 coaxially of the shaft 28 and brake disk 104. A frition ring 107 is interposed between the brake ring 106 and brake disk 104 and is preferably affixed to the former.

The brake 91 frictionally engages the spring arm 66 to the main shaft 28 and, hence, to the club arm 34 and drive arm 61. Thus, during the backswing and foreswing, the brake 91 is not subjected to torques since the spring arm 66 is connected to the drive arm 61 and hence to the shaft 28 through the latch 81. On the other hand, when the drive arm 61 overruns the latch 81 during followthrough due to the slowing of the spring arm 66, relative movement between the spring arm 66 and shaft 28 necessarily takes place and the brake 91 is called upon to decelerate the shaft 28. If the centrifugal weight 102 is included in the brake, the braking force thereof will be greater at higher main shaft speeds and will lessen the lower main shaft means. Thus, during followthrough, the club arm 34 is frictionally retarded with respect to the spring arm 66 by the brake 91 and the spring arm 66 is in turn resiliently urged against moving with the club arm 34 through followthrough by the spring 71. In this manner, the club arm 34 is slowed and is preferably stopped before it reaches a top dead centered position, the spring 71 and the weight of the club arm and the club tending thereafter to cause the club arm 34 to return in a clockwise direction to a position near its downwardmost position shown in FIGURE 2.

Turning now to the wrist device generally indicated at 38 in FIGURE 1A and disclosed in more detail in FIG- URES 7-10, same is mounted at the lower end of the club arm 34. The lower end of the club arm 34 is notched as indicated at 111 (FIGURE 7) to define parallel rearward and forward webs 112 and 113 between which the wrist device is disposed. The webs 112 and 113 have centered, coaxial openings 116 and 117, respectively, therethrough. Coaxial stub shafts 118 and 119 are snugly disposed in the openings 116 and 117, respectively, and extend inwardly into notch 111 a short ditsance. The stub shafts 118 and 119 are restrained from outward axial movement with respect to the arm 34 by retainer plates 121 and 122 secured to the outer surfaces of the webs 112 and 113, respectively, by screws 123. An elongated generally rectangular shell 126 is disposed between the webs 112 and 113 and has a central opening 125 extending longitudinally therethrough. The shell 126 carries intermediate its ends a coaxial pair of ball bearings 127 and 128 aligned diametrically of the central opening and snugly disposed in outwardly opening recesses 131 and 132 in the periphery of the shell 126. The inner ends of the stub shafts 118 and 119 are snugly received within the respective bearings 127 and 128 for pivotally supporting the shell 126 for rotation about the axis thereof and, hence, within the plane of motion of the arm 34. Pivotal movement of the shell 126 with respect to the club arm 34 simulates the hinging action of a golfers wrist and in this sense the bearings 127 and 128 and stub shafts 118 and 119 comprise the hinge portion of the wrist means 38.

A generally cup-shaped member 134 (FIGURE 7) is supported for rotation about the longitudinal axis thereof within the shell 126 on bearings 136 and 137 disposed adjacent the ends of the shell 126. The cup-shaped member 134 has a relatively deep, cylindrical and downwardly opening central recess 138 into which the grip G of a club C may be loosely and coaxially received. Thus, the cup-shaped member 134 is supported for rolling motion about the axis of the club shaft and in the plane of the swing of the club arm 34.

A bevel gear 139 is coaxially aflixed to the upper end of the cup-shaped member 134 by any convenient means here comprising screws 141. The teeth 142 of the bevel gear 139 mesh with corresponding teeth 143 of a further bevel gear 144 which is arranged coaxially of the stub shaft 119 between the web 113 and the bearing 128. The further gear 144 is fixed to the inner face of the web 113, in the particular embodiment shown, by the screws 123 securing the plate 122 to the web 113 which extend through the beveled gear 144 to threadedly engage a retaining ring 146 coaxially disposed on the inner face of the beveled gear 144. The bevel gears 139 and 144 interconnect the rolling cup-shaped member 134 and the lower end of the club arm 34 so that the rolling motion of the cup 134 is a function of the hinging motion of the shell 126 with respect to the club arm 34. More particularly, the bevel gears 139 and 144 are, in the particular embodiment shown, of equal diameter and, therefore, rotation of the shell 126 through a given angle with respect to the arm 34 will produce a rotation through the same angle if the cup-shaped member 134 with respect to the shell A gripping member 151 is secured to the open lower end of the cup-shaped member 134. In the particular embodiment shown in FIGURES 710, the lower end of the cup-shaped member 134 is provided with an integral radial flange 152. The gripping member 151 (FIGURES 8 and 10) comprises an elongated rigid metal sheet generally of V-shaped cross section indicated at 153. The sheet 153 is provided with transverse flanges 154 at its upper end. The flanges 154 are secured to the lower radial face of the flange 152 by screws 156 so that the sheet 153 extends axially away from the open end of the cup-shaped member 134. The V-section sheet 153 has oppositely and outwardly extending coplanar flanges running axially therealong as indicated at 157 and 158.

A cover block 159 (FIGURE 10) extends axially along the V-shaped sheet 153. The cover block 159 is provided with a V-shaped, longitudinal groove 161 opposite the center of the V-shaped sheet 153. Screws 162 are disposed at spaced locations along the flanges 157 and 153 and extend therethrough and through the cover block 159 adjacent edges thereof. Wing nuts 163 are threaded on the ends of the screws 162. Thus, the grip G of a golf club C may be inserted between the center of the V- shaped sheet 153 and the V-shaped groove 161 in the block 159 with the upper end thereof lying, as above mentioned, within the recess 138 of the cup-shaped member 134. The wing nuts 163 may then be tightened to bring the cover block 159 evenly and firmly against the grip G of the club in a manner to fix the club C to the wrist device 38.

9 Operation Although the operation of the apparatus 10 has been disclosed to some extent hereinabove, same will be briefly reviewed hereinbelow to insure a complete understanding of the invention.

The apparatus 10 can be adjusted for providing the proper angle between the club shaft S and the base 11 by positioning the pin 23 and the rear end of beam 13 at a different one of the holes 22 in the member 21. Also, clubs of different shaft lengths are readily accepted by altering the longitudinal position of the end of the club grip within the recess 138 of the cup-shaped member 134.

With a club C firmly affixed, as above described, the gripping member 51 and a ball B in place as disclosed in FIGURE 2 upon the platform 39 in line with the path of the club head H, operation of the apparatus 10 may be initiated by closing the switch 46 to energize the motor 42.

The motor shaft 43 rotates the driving disk 57 through the gear train 49 to revolve the drive pin 58 in a clockwise direction as seen in FIGURE 4. The drive pin 58 engages the face 89 of the drive arm 61 and causes a corresponding clockwise rotation thereof and of the shaft 28 and club arm 34 afiixed thereto through the backswing portion of the club stroke. As the drive arm 61 moves through the backstroke, it engages the rearward end 85 of the lever arm 84 of the latch 81 and so carries along the spring arm 66, thus stretching the spring 71. During the backswing, the club C is preferably manually hinged in a clockwise direction, as seen in FIGURE 2, on the stub shafts 118 and 119 past a vertical position to simulate the cocking of the wrist of the golfer during the backswing. If desired, the shell 126 may be rested against the edge of the notch 111 on any convenient stop, not shown. Such hinging of the club C with respect to the club arm 34 results in a rolling of the club C about the axis of its shaft S on the bearings 136 and 137 due to interaction of the bevel gears 139 and 144. Thus, the wrist device 38 is cocked with respect to both hinged motion and rolling motion of the club. The top of the backswing is normally at least near the broken line position D in FIGURE 2.

As the drive disk 57 continues to rotate, the drive arm 61 eventually reaches the top of the backswing and is released by the drive pin 58. The stretched spring 71 thereupon strongly accelerates the spring arm 66 and, because of the latch 81, the drive arm 61 and club arm 34 downwardly in a counterclockwise direction through the foreswing. As the club arm 34 begins the foreswing, the club head C is accelerated angularly therewith and is pulled radially outwardly with respect to the axis of the main shaft 28 by centrifugal force as indicated at position E of FIGURE 2, thus hinging on the stub shafts 118 and 119 and moving toward a position of axial alignment with the club arm 34 as the club arm 34 sweeps downwardly toward its depending, solid line position of FIGURE 2. As the hinging continues, the club C is rolled about its shaft S by the gears 139 and 141 so as to bring the face of the head H into the proper relationship with the ball B as such ball is approached and struck. The acceleration of the club arm 34 by the contracting spring 71 di- 'rninishes as the club arm 34 approaches alignment with the ball B.

As the movement of the club arm 34 continues, the

club shaft S advances to a position of axial alignment therewith and then swings therepast as would generally be the case when a competent golfer uncocks his wrists at ball impact. As the club head swings past the axially aligned position, its effective radius of the path of movement decreases, that is, the distance between the axis of main shaft 28 and the club head decreases. Assuming the club arm 34 is not decelerating, the velocity of the club head will increase as its effective orbit radius begins to decrease. Therefore, the club head velocity is generally at its greatest near where it passes a position of axial alignment with the club arm and it is preferable that the ball B be struck by the club head when the latter is at or near maximum velocity. Thus, the club shaft will normally be at or somewhat slightly past a position of angular axial alignment with the club arm 34 as the club head strikes the ball B as shown in solid lines in FIGURE 2.

The foreswing of the apparatus 10, including the point of ball impact, closely parallels the swing that would be given the club by a competent golfer, in the free hinging movement, the rolling movement interlinked with the hinging movement, the maximization of angular club head velocity and its exceeding of angular club arm velocity substantially at ball impact and the straightening of the angle between the club arm and shafts just prior to ball impact. Further, the apparatus 10 has been observed to hit regulation golf balls with a conventional driver to distances of the magnitude 200 yards and has been observed to consistently place balls so hit Within a 30 foot diameter area of ground.

It will be noted that as the arm 34 moves through the followthrough stroke that the club head continues to hinge and advance with respect to the club arm, the Wrist device 38 simultaneously rolling the club shaft to closely simulate the followthrough' stroke of a competent golfer.

After the ball B is struck by the club C and the arm 34 swings in a counterclockwise direction as seen in FIG- URE 2 into the followthrough portion of the stroke, the spring arm 66 and spring 71 soon become axially aligned. Acceleration of the club arm by the spring then stops and the spring 71 begins to decelerate the arm 66 as inertia carries it past such axially aligned position. As the spring arm 66 decelerates, the drive arm 61 moves away from the rear end of the latch arm 84, i.e., overruns the latch 81, due to the inertia thereof and of the club arm 34 and club C. The resulting relative rotation between the rotating shaft 2.8 and the decelerating spring arm 66 is frictionally resisted by the brake 91. Should the centrifugal weight 102 be included, the braking force will be higher for greater rotational rates of the main shaft 28. When the club arm 34 reaches its normal topmost position during followthrough, preferably near or somewhat beyond position F of FIGURE 2, the spring 71 and brake 91 act to stop the club arm 34.

Alternatively, however, the braking force of the brake 91 may be reduced as by removal or replacement of spring 99 with a spring of lesser force so that the club arm 34 continues around through .a full circle or more. In such case, the drive arm 61 may continue its counterclockwise rotation past the spring arm 66, the arm 84 of the latch 81 resiliently pivoting on the pin 83 to allow the drive arm to pass and the spring 86 returning the latch 81 to its rest position of FIGURE 6 thereafter. After the apparatus 10 has come to rest, the apparatus 10 may be reset for a new stroke. To reset the apparatus 10 for a further stroke, the club arm 34 is preferably manually moved to a position near its downwardmost position of FIGURE 2, if it has not returned there by itself, preferably in a clockwise direction, the friction brake 91 preferably having suificient slippage to allow relative movement between the shaft 28 and spring arm 66 within only moderate tensioning of the spring 71. Thereafter, the ball B may be replaced and a further cycle may be initiated as above described.

illodificatians FIGURES 12-14 disclose automatically engaging and disengaging catch 167 actuable to retain the wrist device in a cocked position and for releasing the wrist device to allow uncocking thereof. Parts of the apparatus of FIGURES l2-14 corresponding to parts of the apparatus 10 will carry the same reference numerals thereas with the suffix A added thereto.

An oval planar cam 168 is aflixed to the front of the frame 12A by any convenient means such as'screws, not shown, and parallels the plane of the legs 16A and 17A thereof. The cam 168 has an opening 169 therethrough in which the front main shaft bearing 31A is disposed. The club arm 34A differs from the club arm 34 of the apparatus in being mounted eecentrically offset to the right (FIGURE 12) of the main shaft 28A. More particularly, a mounting block 171 is bolted to the leftward side of the arm 34A at the upper end thereof and snugly receives the main shaft 28 therethrough. Set screws 172 .are tightenable to prevent relative rotation between the shaft 28A and the club arm 34A. In the particular embodiment shown, the arm 34A comprises a channel member, the bight portion 173 of which faces 'leftwardly in FIGURE 12.

The catch 167 includes a bell crank 175 (FIGURE 12). The shaft 174 of the bell crank 175 extends through and is rotatably supported by the rearward flange 176 of the channel-like arm 34A. The rearward end of the shaft 174 has rigidly affixed thereto a radially extending cam follower arm 177 which is seen in FIGURE 12 extends generally upwardly and rightwardly from the verticaly depending arm 34A generally in front of the lower, rightward edge of the cam 168. A roller 178 is rotatably mounted on the rearward face of the cam follower arm 177 at the free end thereof and bears on the periphery 179 of the cam 168. A lever arm 181 is fixed to the shaft 174 in front of the flange 176 and extends leftwardly through an opening 182 in the bight 173.

The catch 167 further includes a generally T-shaped lock member 183 (FIGURES 12, 13 and 14) which includes a crosshead 184 and a leg 186 extending generally downwardly therefrom and angling somewhat to the left as seen in FIGURE 12. The rightward end of the crosshead 184 is mounted by a screw 187 and nut 188 on the rear flange 176 of the club arm 34A adjacent the lower end thereof and extends leftwardly through an opening 189 in the bight 173 so that the leg 186 and the leftward portion of the crosshead 184 are located to the left of the club arm 34A. The lock member 183 is planar and parallels the rear flange 176. A spacer 191 on the screw 187 spaces the lock member 183 forwardly of the flange 176. The lower end of the leg 186 is provided with a generally rightwardly opening hook indicated at 192.

The leftward end of the crosshead 184 is pivotally affixed to the lower end of a transfer bar 193 by a screw 194. An internally threaded, elongated and cylindrical sleeve 196 (FIGURES 13 and 14) is threaded onto the rearward end of the screw 194 to retain the transfer bar 193 thereon and, further, for purposes described hereinafter. The transfer bar 193 extends generally upwardly and is sloped slightly to the rear as seen in FIGURES 13 and 14. The upper end of the transfer bar is pivotal'ly connected to the free end of the lever arm 181 by a screw 197 and nut 198.

A latch restraining lever 199 is pivotally mounted intermediate its ends by a screw 201 aflixed to a boss 202 (FIGURE 13) extending leftwardly (FIGURE 12) from the club arm flange 176 and spaced a short distance above the generaly T-shaped lock member 183. The latch restraining lever 199 extends from the screw 201 rightwardly (FIGURE 12) through the opening 189 into the arm 34A along the flange 176. The leftward end 204 of the latch restraining lever 199 extends past and above the leftward end of the crosshead 18 4 of the lock member 183. The lower edge 206 of such leftward end 204 slideably bears upon the sleeve 196. The latch restraining lever 199 slopes upwardly and toward the right. A generally rightwardly opening hook-shaped notch 207 is provided in the lower edge 286 adjacent the leftward edge of the club arm flange 176.

A tension spring 288 (FIGURE 12) is connected between the rightward end of the latch restraining lever 199 and the lever arm 181 intermediate the ends thereof, such spring extending through the bight 173 at an opening 209 therethrough. The spring 208 acts through the bell crank to press the roller 178 snugly against the periphery 179 of the cam 168. Simultaneously, the spring 208 exerts a counterclockwise torque on the latch restraining lever 99 so as to maintain the lower edge 286 there firmly against the sleeve 196 and thereby urge the T-mernber 183 downwardly.

An angle guard 211 is affixed to the bight 173 behind the transfer bar 193 and extends from a point above the latch restraining lever 199 to a point spaced below the arm 181 to protect the transfer bar 193.

A generally planar insertion plate 212 is fixed by any convenient means such as screws, not shown, to the rearward side of the shell 126A within the web 112A. As seen in FIGURE 12, the insertion plate 212 extends leftwardly and downwardly from the hinge axis of the shell 126A and has a generally leftwardly extending end portion 213. A flange 214 is formed preferably integrally with the upper edge of the end portion 213 and it extends forwardly therefrom through the plane of the T-shaped lock member 183 located thereabove. The flange 214 is preferably sloped slightly upwardly and to the right as seen in FIGURE 12. A locking pin 216 extends forwardly from the end 213 and is spaced beneath the rightward edge of the flange 214. The pin 216 also extends through the plane of the T-shaped lock member 183.

The latch 167 allows the wrist device 38A to be manually hinged to a cocked position, here approximately at right angles to the longitud nal extent of the club arm 34A, as illustrated in broken lines at position A of FIG- URE 12. The latch 167 holds the wrist device 38A in such cocked position until the club arm 34A has rotated through and has reached the top of its backswing at which point the latch 167 releases the wrist device 38A to allow same to uncock during the foreswing as above described with respect to the apparatus 10. More particularly, with the arm 34A in its lowermost position shown in solid lines in FIGURE 12, manual pivoting of the wrist device 38A in a clockwise direction about the axis of stub shaft 119A eventually brings the leftwardend of the flange 214 into sliding contact with the lower end of the leg 186 of the lock member 183. Continued clockwise movement of the wrist member 38A causes the leftward end of the flange 214 to move along and lift the lower end 186 to cause a clockwise pivotal movement of the lock member 183 about the axis of the screw 187. Thereafter, the leftward end of the flange 214 passes the hook portion 192 and along the rightward edge of the leg 186 to a position adjacent the lowermost portion of the bight 173 of the club arm 34A as shown in the broken line position A of FIGURE 12. During this movement of flange 214', the locking pin 216 is brought past the lower end of the leg 186 and as the flange 214 moves into adjacency with the bight 173, the pin 216 enters the mouth of the hook 192. The pin 216 is caught by the hook 192 and positively prevents return of the wrist portion 38A to its solid line position of FIGURE 12. The catch 167 is now locked and positively holds the wrist device 38A in its cocked position. It should be noted that during the abovedescribed clockwise movement of the locking member 183, the sleeve 196 rides up the edge 206- but not far enough to enter the notch 207. Thus, the locking memher 183 is allowed to return substantially to its original rest position as the flange 214 approaches the upper end of the leg 186 so that the hook 192 can engage the locking pin 216.

In the particular embodiment shown in FIGURE 12, the cam 168 engages the follower 178 with a somewhat decreasing radius as the arm is moved through the initial part of the backswing through the broken line position A. This allows the locking member 183 to bear positively to the right against the locking pin 216 thereby securely holding the wrist position 38 in its cocked position as a result of the force of the spring 208 exerted through the restraining lever 199 upon the locking member 183. However, as the club arm 34A approaches the end of the back- 13 a swing, the club C extending at least somewhat to the right from the wrist device, the roller 178 encounters a portion 217 of increased radius on the cam 168. This causes be-ll crank 175 to pivot in a clockwise direction to its broken line position B of FIGURE 12. The transfer bar 193 is thereby pulled toward the main shaft 28A to effect a corresponding clockwise movement of the locking member 183 sufficient that the locking pin 216 will be released by the hook 192 thus unlocking the catch 167. The flange 214 will normally rest against the lowermost bight portion 173 of the arm 34A to limit further clockw'se movement of the wrist device 38A, the force of gravity on the wrist device and the club held thereby preventing uncocking of such wrist device at this point.

As the club arm 34A more closely approaches the end of the backswing. the cam portion 217 rises further and through the bell crank 175 and transfer bar 193 causes further clockwise movement of the locking member 183 which moves the sleeve 196 upwardly along the edge 206 of the latch restraining lever 199 and into the notch 207 thereof. This engagement of the sleeve 196 and notch 207 prevents counterclockwise returning movement of the locking member 183 independent of any movement of the follower roller 178 on the cam during the foreswing. As a result, the locking member 183 is prevented from reengaging the locking pin 216 and the catch 167 is unlocked.

At some point thereafter, the backstroke motion will end and the forestroke wiil begfn. As the arm 34A moves into its forestroke, the resulting centrifugal acceleration of the club head H causes the wrist device 38A to begin counterclockwise uncockin-g movement with respect to the arm 34A as described hereinabove with respect to the apparatus 10.

To ready the catch 167 for another cycle of use, the sleeve 196 is released from the notch 207 by momentarily lifting the left-hand end 204 of the latch engagng member 199 whereupon the spring 208 through the transfer bar 193 returns the locking member 183 to its counterclockwisemost position shown in solid lines in FIGURE 12. Release of the latch restraining lever 199 allows the spring 208 to urge the edge 206 thereof against the sleeve 196 which firmly holds the locking member 183 in its counterclockwisemost or rest position shown for future engaging of the locking pin 216 as discussed hereinabo-ve.

FIGURES 15 and 16 disclose a modified forestroke spring drive and followthrough braking arrangement. Parts of the modified apparatus of FIGURES 15 and 16 corresponding to the apparatus of FIGURE 1 will be referred to by the same reference numerals thereas w'th the sufiix B added thereto. The apparatus of FIGURES and 16 includes a secondary spring system 220 compris'ng a parallel pair of tension springs 221 and 222 connected between the bolt 72B fixed to the frame leg 17B and a spring arm 219 rotatable on the main shaft 283.

As shown in FIGURE 16, a primary spring system generally indicated at 223 is provided between the secondary spring system 220 and the rear bearing 32B of the shaft 288. The primary spring system 223 comprises a further spring arm 224 rotatable on the shaft 283. The spring arm 224 has a rigid finger 226 near the free end thereof which parallels the shaft 288 for engaging the upper surface of the drive arm 61B in a manner similar to the latch 81 of FIGURE 6. Thus, when the drive arm 61B is moved through its backswing, the spring arm 224 must follow.

A bar 228 is axially slideable through a boss 229 on the upper face of the spring arm 56B adjacent the free end thereof. The bar 228 is manually movable into the path of the spring arm 224 as shown in FIGURE 16 for causing the spring arm 219 to follow the spring arm 224 through the backswing. Alternatively, the bar may be retracted to allow the spring arm 219' to remain at rest while the spring arm 224 and drive arm 61B move together through the backstroke.

The springs 221, 222 and 231 are secured to the free ends of their respective spring arms 219 and 234 preferably in a manner similar to that in which the spring 71 is secured to the arm 66 of FIGURE 6.

The lower end of the spring 231 secured to a fine adjustment device 232 which is manually actuable to set within relatively close limits the tension of the spring 231 and, hence, the force imposed thereby upon the spring arm 224 and drive arm 61B. In the particular embodiment shown, the fine adjustment device 232 comprises a bearing 233 which is in turn secured by a bracket 234 to the rear face of the leg 17B adjacent the bolt 72B. The bearing 233 carries a shaft 236 rotatable therewithin. A manually adjustable hand wheel 237 is secured to the rear end of the shaft 236 and a pinion gear 238 is affixed to the forward end of the shaft 236. An elongated rack 239 is slideably mounted at the forward end of the bearing 233 for movement substantially along the axis of the spring 231 by any convenient means substantially indicated at 241 in FIGURE 15. The teeth 242 of the rack 239 are engaged by the pinion 238 so that rotation of the hand wheel 237 will cause, through the pinion 238, a corresponding axial movement of the rack 239 and a consequent tensioning or loosening of the spring 231. Thus, I

the fine adjustment mechanism 232 provides a way to precisely adjust the velocity characteristic of the club during the foreswing. A latch 243 is provided for locking the rack 239 in a preselected position so that the hand wheel 237 may be released without allowing movement of the rack in response to the tensioning of the spring 231. More particularly, latch 243 comprises a single toothed bar 244 pivotally mounted on the underside of the bearing 233 as indicated at 246 for engaging opposed ones of the teeth of the rack.

In operation, the bar 228 would normally be moved to its leftwardmost position out of engagement with the spring arm 224 when a relatively low club head velocity is required, the fine adjustment mechanism 232 allowing a precise selection of such velocity. On the other hand, when higher club head velocities required, for example, for driving golf balls to a distance comparable to that of a competent golfer, the bar 229 may be moved rightwardly to engage the upper surface of the spring arm 224 thereby paralleling the springs 221 and 222 with the spring 231 to provide additional torque on the shaft 2 8B during the forestroke.

The modified braking device 251 disclosed in FIG- URES 15 and 16 would normally be used with the modified spring drive thereof instead of the friction brake 92 hereinabove described. More particularly, the modified brake 251 provides for positively stopping the followthrough stroke of the club well before a complete revolution occurs and thereby prevents the drive arm from striking the back of the rigid finger 226. The brake 251 comprises a brake arm pivotally afiixed at one end thereof to the shaft 283 between the bearing 32B and the drive arm 61B. The brake arm 251 mounts a rearwardlyextending pin 253 adjacent its free or lower end which overlaps the path of the drive arm 61B. The brake arm 251 is normally disposed in a depending, somewhat rightwardly angled position as seen in FIGURE 16. The free end of the brake arm 251 is pivotally aflixed to the piston rod 254 of a braking fluid cylinder 256 the lower end of which is pivotally secured as indicated at 257 in FIG- URE 15 to the bracket 234. The axis of the cylinder 256 extends upwardly and is angled somewhat rightwardly to its connection with the brake arm 252. The drive arm 61B strikes the pin 253 during the early part of the followthrough and drags the brake arm 252 along therewith, the brake arm motion being retarded by the cylinder 256. As the followthrough stroke advances, the piston rod 254 will approach a right angle inclination with respect to the brake arm 252 thus bringing to a maximum the retarding torque exerted on the drive arm 61B and shaft 28B during followthrough by the cylinder 256. The cylinder 256 is preferably of sufilcient length as to allow a followthrough stroke of length at least approaching that of any competent golfer. Followthrough movement preferably substantially abates before the piston rod 254 is fully extended. The cylinder 256 preferably allows the club arm 34B to return to its normal depending rest position of FIGURE and in fact may be spring biased to retract.

FIGURES l7 and 18 disclose modified anchor means 261 for securing the upper end of a spring 71C to the spring arm 66C. The anchor means 261 differs primarily from the spring anchoring core 74 of FIGURE 6 in that the anchor means 261 is more quickly releasable from the arm 66C for rapid adjustment of its position in the holes 79C along said arm. More particularly, the apparatus 261 comprises a pair of stub shafts 262 and 263 snugly but slideably disposed Within a sleeve 264 which sleeve is disposable between the side walls of the spring arm 66C. Radial pins 266 and 267 extend from the intermediate portion of the stub shafts 262 and 263, respectively,

through aligned axial slots 268 and 269 in the shell 264.

The stub shafts 262 and 263 are urged apart by a coaxial compression spring 271 to the extent allowed by the engagement of the pins 266 and 267 with the outer ends of the slots 268 and 269 and so that the outer reduced diameter ends thereof extend into opposite ones of the holes 79C to securely pivotally mount the anchor means 261 in the spring arm 266C. The holes 79C are preferably bushed as indicated at 276. Axially spaced lugs 277 and 278 depend from the shell 264 and are connected by a bolt 279 fixed in place by a nut 281. The upper end of the spring 71C is wrapped around the bolt 279, thereby being secured to the anchor means 261.

FIGURES l920 disclose a modified club gripping member 151D. The gripping member 151D comprises an elongated substantially V-shaped cross section sheet 153D having mounting flanges 154D at the leftward end thereof, the sheet 153D and flanges 154D corresponding generally to similarly numbered parts of FIGURE 8. A clamping member 282 is of generally V-shaped inverted cross section and extends along and substantially through the length of the sheet 153D. The leftward end of the clamping member 282, is pivotally connected as indicated at 283 to ears 284 extending upwardly from the side edges of the sheet 153D adjacent the leftward end thereof. With the clamping member 2 82 pivoted away from the sheet 152D, the grip G of a golf club C may be inserted axially thereinto as indicated in broken lines in FIGURES 19 and 20. A leftwardly tapered radial fin 286 extends from point near the rightward end of the clamping member 282 leftwardly to the end thereof along the apex thereof. Similar fins 287 and 288 are axially aligned with the fin 286 and fixed to the side faces of the sheet 153D at spaced locations. The fins 286 through 288 are circumferentially threaded, except for a portion at the leftward end of each thereof, for receiving an internally threaded ring 289 in threaded engagement therewith. The ring 289 is provided with manually engageable radial pins 291. Thus, to tighten the gripping member 151D upon the grip G of the golf club, the ring 289 is moved rightwardly over the members 153D and 2 82 until it contacts the threaded portions of fins 286 through 288. The ring 289* is then manually rotated to thread same rightwardly along such fins, the taper of the fins causing the member 282 to pivot toward the sheet 152D to tightly grip the grip G of the golf club C therebetween.

FIGURE 21 discloses a preferred embodiment of a club head speed measuring device generally indicated at 301 arranged for measuring the speed of the head H of the club C as it approaches the golf ball B. The device 301 includes a platform of the type described hereinabove with respect to FIGURE 1 and indicated here at 39E. The platform 39E houses a vertically spaced series of horizontal baffles 302. A vertically aligned series of holes 303, preferably slots elongated transversely of the club head path, extend downwardly from the top 304 of the platform 39E through the lowest ones of the bafiie 302. The slots 303 are spaced from the ball B along the foreswin g path of the club head H. A similar vertically aligned series of transverse slots 306 extends through the top 304 and baffles 302 at a location between the slots 303 and ball B. Suitable photoresponsive means, here photocells 307 and 308, are disposed in the platform 39E below the series of slots 303 and 306, respectively. The light passing through the series of slots 303 and 306 and striking the photocells 307 and 308 may be provided by lamps, not shown, mounted above the club head H or may simply be available light in the area in which the apparatus is being used. In any event, the vertical alignment and spacing of the slots 303 and 306 results in effective columnization of the light striking the photocells. Thus, in effect, the only light striking the photocell 307 that in a vertical beam 311 in alignment with the slots 303 and the only light striking the photocell 308 will be that in a vertical beam 312 aligned with the slots 306. Therefore, as the club head H approaches the ball B it will first break the light beam 311 striking the photocell 307 and thus reduce the level of light, impinging thereupon and at a time thereafter determined by the average speed of the club head between the slots 303 and 306, said club head will break the beam 312 and sharply drop the level of light falling upon the photocell 308. DC. anode potential is supplied to the photocells from a source V of a conventional type. The cathodes of the photocells 307 and 308 are connected to suitable transistor amplifiers generally indicated at 313 and 314, respectively. The amplifiers are preferably identical and hence only one thereof, for example the amplifier 313, will be described in detail. More particularly then, the cathode of the photocell 307 is connected to the base of a transistor 316, the emitter of which is connected to the base of the further transistor 317. The emitter of transistor 317 is grounded. Positive operating potential is supplied to the collectors of the transistors 316 and 317 through supply resistors 318 and 319 from any convenient source of positive potential, not shown. The amplifier output is taken from the collector of the second transistor 317 through a capacitor 321, the output side of which is grounded through a dropping resistor 322, and applied through a line 323 to one of the inputs of a bistable circuit 324. The output line 326 of the amplifier 314 is connected to the other input of the bistable circuit 324.

Thus, when the light striking the photocell 307 drops due to breaking of the beam 311 by the club head H, the current flow therethrough also drops. This diminishes the current flow through the transistors 316 and 317 and thus produces a rising potential on the collector of the transistor 317 which through the action of the capacitor 321 provides a positive pulse through the line 323 to the bistable circuit 324. The positive pulse on the line 323 reverses the state of the bistable circuit 324.

Similarly, passing the club head through a beam of light 312 produces a positive pulse in the output line 326 of the second amplifier 314 and returns the bistable circuit to its rest state.

The alternating output of an oscillator 327 of any convenient type having a known, constant frequency output, conveniently of single polarity pulses, is fed through a gate circuit 328 to a pulse counting device 329 of any convenient type here a binary counter. The oscillator gate is controlled by the output of bistable circuit and thus by the conductive state of the photocells 307 and 308. Therefore, as the club head breaks the beam 311, the bistable circuit 324 turns on the oscillator gate 328 to allow pulses from the oscillator 327 to be fed to the'binary counter 329. The oscillator gate maintains the oscillator in connection with the binary counter 329 until the club head H breaks the second beam of light 312 which causes the bistable circuit 324 to shut the gate 328 and thereby stops the flow of pulses to the binary counter 329. The binary unter 3. 9 feeds a suitable count indicator 331 which may be a series of lights actuable to indicate the number of pulses applied to the binary counter. Thus, the display of the indicator is a direct function of the period during which the moving club head H is between the beams 311 and 312 and, hence, is a known inverse function of the average club head speed.

FIGURE 22 discloses a modified speed measuring device 334 generally similar to the device 301 except that a ball B and club head H are disposed above a plate which may for example be the base plate 11F of the apparatus and the platform 39B is spaced above the path of the club head H as it nears the ball B. The platform 39E and the circuitry associated therewith are otherwise similar to that disclosed in FIGURE 21 above discussed and need no further dicussion here. The plate 11F is furnished with a pair of slots 36 and 37 coaxially aligned with the slots 303E and 306E. Lamps 338 and 339 are disposed below the plate 11F in alignment with the holes 336 and 337, respectively, and are connected to a suitable source power, not shown, for furnishing beams of light 341 and 342, respectively, through the slots 336, 337 and 303E, 306E to the photocells 307E and 308E. As in the case of the apparatus of FIGURE 21, movement of the club head H toward the ball B successively breaks the beams 341 and 342 as a result of which the phototubes 307E and 308E respectively actuate suitable counting means as described above with respect to FIGURE 21.

Although particular preferred embodiments of the invention have been disclosed above for illustrative purposes, it will be understood that variations or modifications thereof which lie within the scope of the appended claims are fully contemplated.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In an apparatus for swinging a golf club through a stroke, the combination comprising:

a frame;

a club arm mounted for pivotalmovement with respect to said frame and means for swinging said club arm; mounting means for movably mounting a golf club on said club arm for hinging movement substantially in the plane of arm rotation and for-rolling movement generally about the axis of its handle as it is hinged.

2. In an apparatus for swinging a golf club through a golf stroke, the combination comprising:

a frame;

a club arm mounted for rotation with respect to said frame;

means for rotating said club arm at least through the foreswing of a golf stroke;

wrist means hinged freely on said arm for pivotal movement with respect thereto substantially within the plane of rotation of said club arm;

rolling means rotatably fixed to said Wrist means and interconnected therewith for rolling movement with respect thereto as a function of the hinging motion of said wrist means on saidclub arm;

club gripping means on said rolling means carrying said golf club with the handle thereof generally aligned along an axis of said rolling movement;

whereby rotation of said club arm through said foreswing results in hinging motion of said club with respect to said club arm and rolling motion of said club about the axis of its handle as a function of said hinging motion.

3. The device defined in claim 2 including a main shaft rotatably mounted on said frame, said club arm being affixed to said main shaft for rotation therewith with respect to said frame; and

a drive arm fixed to said main shaft and motor means engageable with said drive arm for automatically moving said club arm to the top of the backswing and releasing same to allow said arm to be moved through the foreswing.

4. The device defined in claim 2 which said means for rotating said club arm through said foreswing comprises a main shaft rotatably supported on said frame and fixedly supporting said club arm with respect thereto;

a spring arm pivotally mounted upon said shaft and overrunning latch means for securing said spring arm for rotation with said shaft at least during the backswing and foreswing of the golf stroke and for allowing the shaft to overrun the spring arm rotatably during followthrough;

spring means disposed between said spring arm and said frame for resiliently resisting rotation of said spring arm through said backstroke and for urging said spring arm through said forestroke.

5. The device defined in claim 2 including brake means connected at least indirectly between said main shaft and said frame and means responsive to the position of the club arm with respect to said frame for actuating said brake means to slow the rotation of the club arm during followthrough.

6. The device defined in claim 2 in which said wrist means comprises an elongated hollow shell pivotally mounted on one end of said club arm for rotation about a hinge axis parallel to the axis of rotation of said arm and transverse to the longitudinal axis of said shell;

said rolling means comprises generally cup-shaped member disposed within said shell for rotation about the longitudinal axis of said shell;

.including a first bevel gear fixed to said club arm and coaxial with the hinge axis of said shell and a second bevel gear fixed to one end of said cup-shaped memher and in toothed engagement with said first bevel gear;

whereby pivotal movement of the shell with respect to the club arm causes said first bevel gear to rotate said second bevel gear and therewith said cup-shaped member about the longitudinal axis of said shell.

7. The device defined in claim 2 including catch members on said wrist means and said club arm actuable for maintaining said wrist means in a cocked position with respect to said arm;

cam means fixed with respect to said frame adjacent said club arm;

means responsive to the relative position of said cam means. and club arm for disconnecting said catch means so as to allow free hinging movement of said wrist means with respect to said club arm.

8. The device defined in claim 2 including means fixed with respect to said frame adjacent the path of the head of the golf club for determining the average speed of the golf club head as it passes thereby.

9. In an apparatus for swinging a golf club through a sequence of backswing, foreswing and followthrough in a manner simulating the swing of a competent golfer, the combination comprising:

a frame;

motor means mounted on the frame;

a main shaft rotatably mounted on said frame, a drive arm fixed thereon and drive means releasably connecting said motor means to said drive arm for rotating same through a preselected backswing path and releasing same at the end of said backswing path;

a radial club arm fixed to the end of said main shaft for rotation therewith in a radial plane;

wrist means hinged freely on the free end of said arm for pivotal motion with respect thereto in said radial plane;

means for releasably gripping the handle of a golf club, said club gripping means being rotatably fixed to said wrist means for rolling movement with respect thereto about the axis of theclub handle;

interacting means on said free arm end and gripping means for controlling the roll position of said gripping means on said wrist means as a function of the hinged position of said wrist means on the end of said arm;

a spring arm rotatably supported on said main shaft;

an overrunning latch for engaging said spring arm to said drive arm during the backswing of said drive arm but allowing said drive arm to move away from said spring arm during followthrough;

spring means disposed between said spring arm and frame for input of potential energy thereto by said spring arm during said backswing and for urging said main shaft through the foreswing upon release of said drive arm by said drive means;

brake means having one portion fixed with respect to main shaft and a further portion at least indirectly connected to said frame actuable during followthrough to slow the motion of said club.

10. The device defined in claim 9 in which said drive means comprises a gear train connected at one end thereof to said motor means;

a disk rotatably supported on said frame and rotatably driven by said gear train and a pin mounted on said disk, said pin extending substantially parallel to said main shaft and axially overlapping said drive arm, the axis of said disk being parallel to the axis of said main shaft and displaced therefrom in a direction toward the path of the club head during the intermediate part of the backswing, the area mapped by said drive arm as it rotates about the axis of said main shaft overlapping only a portion of the orbit of said drive pin whereby said pin moves said drive arm through the backswing and releases same at the top of the 'backswing whereat said pin enters the portion of said orbit not overlapped by the area mapped in a revolution of said drive arm.

11. The device defined in claim 9 in which said frame includes a pair of legs between which said main shaft is disposed;

said spring means comprises a helical tension spring and including means for connecting one end thereof alternatively to a plurality of locations on one of said legs;

releasable means fixed to said spring arm adjacent one end thereof and alternatively positionable along the length thereof for pivotally engaging the remaining end of said spring thereto;

said overrunning latch comprising a latch arm pivotally mounted on said spring arm and extending into the path of said drive arm, means resiliently opposing pivotal motion of said latch arm in one direction and further means rigidly preventing pivotal motion of said latch arm in the opposite direction so that said drive arm will, through engagement with said latch means, pull said spring arm through the backswing and can pass the spring arm when moving in the opposite direction. 12. The device defined in claim 9 in which said spring means comprises a tension spring fixed to said spring arm; and

including a further spring arm pivotally mounted on said main shaft adjacent said first-mentioned spring arm, said first-mentioned spring arm being located between said further spring arm and said drive arm;

overrunning means for releasably engaging said firstmentioned spring arm to said further spring arm for allowing said drive arm to move both of said spring arms through said backstroke;

at least one further tension spring affixed to and between said further spring arm and said frame for exerting a torque on said further spring arm, said further spring generally paralleling said first-mentioned spring;

continuously adjustable rack and pinion means for securing said first-mentioned spring to said frame and manually actuable for continuously adjusting the tension of said first-mentioned spring.

13. The device defined in claim 9 in which said spring means comprises at least one tension spring fixed at one end thereof to said spring arm; and including a rack slideably mounted with respect to said frame along the axis of said tension spring and having the remaining end of said tension spring secured thereto;

a manually rotatable pinion gear engaging said rack for varying the axial location thereof and thereby the tension of the spring; and

a manually actuable stop for preventing unintended axial motion of said rack.

14. The device defined in claim 9 in which said brake means comprises a brake arm rotata-bly fixed to said main shaft and located adjacent said drive arm, said brake arm including means extending into the path of said drive arm so that when said drive arm moves through the followthrough portion of the stroke said brake arm will be carried along therewith;

a fluid cylinder pivotally disposed between the free end of said brake arm and said frame for resiliently resisting motion of said brake arm at least in one direction corresponding to the direction of said drive arm during followthrough, the axis of said cylinder lying tangent to the path of the end of the brake arm at an intermediate point thereon.

15. The device defined in claim 9 in which said brake means comprises sleeve means fixed to said main shaft adjacent said spring arm;

pressure plate means circumferentially fixed with respect to said sleeve but axially slideable therealong adjacent said spring arm;

backing plate means fixed with respect to said spring arm and opposed to said pressure plate means;

friction means disposed between said pressure plate means and backing plate means;

pivotal means bearing on said pressure plate means and resilient means for urging said pivotal means against said pressure plate means to urge same against said frictional means and backing means in order to frictionally resist relative movement between said spring arm and said shaft.

16. The device defined in claim 15 in which said pivotable means includes an arm generally paralleling said main shaft and extending away from said pressure plate means and a weight disposed on the free end of said arm, said weight reacting to centrifugal force generated by rotation of said main shaft for assisting said resilient means and urging said pressure plate means toward said backing plate means.

17. The device defined in claim 9 in which the wrist end of said club arm comprises a generally Ushaped notch opening along the direction of pivotable movement of said club arm; and including a coaxial pair of stub shafts mounted on the wrist end of said arm and extending into said notch; in which said wrist means comprises an elongated shell loosely disposed in said notch and carrying a diametrally aligned pair of bearings intermediate the ends thereof, said shell being freely hinged on the inner ends. of said stub shafts by said bearings; and in which said gripping means includes an elongated, generally cup-shaped member loosely disposed within said shell and extending therethrough and. further bearing means disposed at opposite ends of said shell for rotat-ably supporting said cup-shaped member for rotation about the longitudinal axis of said shell; and in which said interacting means comprises a bevel gear coaxial with one of said stub shafts and aflixed to said club arm on the inner wall of said notch and a further bevel gear affixed to the closed end of said cupshaped member and engageable with the first mentioned beveled gear, said beveled gears being of substantially equal diameter so that pivotal movement of said shell about the axes of said stub shafts,

through a given arc will result in rolling of the cupshaped member within said shell through a substantially equal are, said first-mentioned beveled gear being located on the forward side of said shell so that clockwise hinging of said shell as seen from the front of said apparatus results in clockwise rolling of said club as seen from the handle end thereof.

18. The device defined in claim 9 including interengageable catch means on said arm and wrist means manually actuable for fixing said wrist means in a cocked position with respect to said arm and means responsive to the position of said club arm for releasing said catch means.

19. The device defined in claim 18 in which said interengageable catch means on said arm and wrist means comprises a locking member pivotally connected to said club arm adjacent said wrist means and carrying a hook and an insertion plate fixed to said wrist means including transversely extending means, said locking member including surfaces slideably engageable with said transversely extending means for guiding said transversely extending means into retained engagement with said hook upon hinging of said wrist means to a cocked position with respect to said club arm and thereby locking said club arm in said cocked position; and

wherein said means for releasing said catch means includes a cam fixed to said frame and surrounding said main shaft adjacent said club arm, a bell crank pivotally mounted on said club arm adjacent said cam, follower means on one end of said bell crank for riding the periphery of said cam, linkage for connecting the other end of said bell crank to said locking member so that displacement of said follower means away from the center of said main shaft by said cam disengages said hook from said transversely extended means and unlocks said wrist means from its cocked position, a latch restraining lever pivotally mounted on said club arm above and adjacent said locking member, said latch restraining lever having an edge bearing upon said locking member at its connection to said linkage, a notch in said edge between such bearing point and the pivot point of said latch restraining lever and a tension spring connected between the end of said bell crank connected to said lock member and the free end of said lacth restraining member for simultaneously urging said follower means against said cam and said edge against said locking member, the rise of said cam being sufiicient to urge the locking member along said edge of said latch restraining lever into said notch to prevent return of said hook into engagement with said transversely extended means.

20. The device defined in claim 9 in which said means for releasably gripping the handle of said golf club includes rolling member fixed rotatably to said wrist means, a first elongated member extending axially therefrom and a second elongated member substantially paralleling the first elongated member and pivotally affixed thereto adjacent said rolling member, said first and second elongated members defining a cavity of variable cross section therebetween into which the grip of a golf club may be inserted, said first and second elongated members each having at least one substantially radially extending fin running axially therealong, said fins being tapered toward the wrist means, at least the ends of each of said fins farthest from said wrist means being circumferentially threaded and a nut threadable along said fins for tightening said first and second elongated members against the grip of a golf club.

21. The device defined in claim 1 in which the mounting means includes first means for movably mounting a golf club on said club arm for hinging movement substantially in a plane of arm rotation and a second means located between said golf club and said club arm for rotat- 22 ing said golf club about the axis of its handle as it is hinged.

22. In an apparatus for swinging a golf club through a stroke, the combination comprising:

a frame; a club arm mounted for pivotal movement with respect to said frame; means for swinging said club arm; support means for movably mounting a golf club on said club arm for rolling movement about the longitudinal axis of the golf club handle and for swinging movement in a plane substantially parallel to a plane as defined by the swinging movement of said club arm; and means interconnecting said support means with said club arm for causing rolling movement of the golf club about the longitudinal axis of said handle whenever said club arm is swingably displaced. 23. In an apparatus for swinging a golf club through a stroke, the combination comprising:

a frame; a club arm mounted for pivotal movement with respect to said frame; a golf club mounted for pivotal movement on said club arm; first drive means for rotating said club arm through the foreswing of a golf stroke; second drive means for moving said club arm to the top of the backswing of said stroke; and means for releasing said club arm from said second drive means for permitting said first drive means to rotate said club arm through said foreswing. 24. The device as defined in claim 23 wherein said golf club is mounted on said club arm for free hinging movement relative thereto.

25. In an apparatus for swinging a golf club through a stroke, the combination comprising:

a frame;

a club arm mounted for pivotal movement with respect to said frame;

means for rotating said club arm at least through the foreswing of a golf stroke;

a spring arm mounted for pivotal movement with respect to said frame;

overrunning latch means for securing said spring arm for rotation with said club arm at least during the backswing of the golf stroke and for allowing the club arm to rotatably overrun the spring arm during followthrough; and

spring means disposed between said spring arm and said frame for resiliently resisting rotation of said spring arm through said backstroke and for urging said spring arm through said foreswing.

26. The device defined in claim 25 including brake means interconnected between said frame and said club arm for slowing the rotation of said club arm during followthrough; and

means responsive to the position of the club arm with respect to said frame for actuating said brake means to slow the rotation of the club arm during followthrough.

References Cited UNITED STATES PATENTS JAMES J. GILL, Primary Examiner. RICHARD C. QU-EISSER, Examiner. I. D. SCHNEIDER, Assistant Examiner. 

